This invention relates to an automatic tape threading device of a magnetic tape system having a supply reel and a takeup reel arranged vertically.
In this specification, the term "threading" refers to passing a magnetic tape wound on a supply reel through a passage facing a magnetic head after paying its leading end portion out of the supply reel to be wound on a takeup reel, and the term "automatic threading" refers to an operation for performing the aforesaid process automatically. Automatic threading is described in detail in for example U.S. Pat. Nos. 3,398,913 and 3,473,042.
For a magnetic tape system including a supply reel and a takeup reel arranged vertically in superposed relation, it has been the usual practice to use a method of automatic threading of the magnetic tape which relies on the force of gravity for inserting the leading end of the magnetic tape payed out of the supply reel to the passage. More specifically, the magnetic tape, payed out of the supply reel slide on a threading, drops by its own weight on to a roller, located at the inlet of the passage, to be transported to a predetermined position.
Some disadvantages are associated with this method of the prior art. For example, when a magnetic tape is allowed to drop by its own weight, the tape is attracted to the roller and jammed. Also, the leading end portion of the magnetic tape, payed out of the supply reel and sliding on the threading chute, tends to pass by the roller by moving thereabove.